Compound metal body.



2 SHEETS-SHEET l.

Pmtnteul Apr. 18, 1916.

0. H. DE LAPOTTERIE.

COMPOUND METAL BODY.

APPLlcATmN FILED MAR. 22, lala.

0. H. DE LAPOTTERIE.

COMPOUND METAL BODY. APPLICATION FILED mmzz. :915.

Patented Apr. 18,1916.

A 2 SHEETS-SHEET 2- OTTO JEL ma LAJPUTTEIE, 0F NEW BRIGHTON, JE'ENNSVANlcenno zu Specincation ot' Lettere tatent.

"t 1"" MJETL UDY.

Patented dpr.. delle@ @riginal application med April 7, 19M, Serial No.@$0,193. Divided and thin application tiled iltareh t2,

191%. ei'ial No. MAM.

To all lwhom t may concern Be it known that l, @Taro H. nr. LAro'r-TERIE, a citizen of the United States, residing at New Brighton, in thecounty of Beaver and State -of Pennsylvania, have invented certain newand useful Improvements in Compound Metal Bodies, of which the followingis a specification.

rllhis invention relates to compound meta-l bodies consisting of unitedlayers or strata of unlike metals, i. e. metals or alloys of unlikechemical nature, so firmly and permanently united that they will resistthe actlon of cleaving tools, violent temperature changes, anddistortion, to vseparate them.

i alloy united, or plain alloy union, without intending thereby to limitor confine myself to any particular theory as to the actual nature ofthe union between the unlike tinguishing. and convenient ones.

By the method hereinafter described it is possible to `produce compoundmetal ingots, and also manufactured articles, of compound metal, such asplates, sheets, rods, tube, wire, and the like, and the same maybeeither the product of the compound metal ingot extended by drawing,rolling, pressing, hammering, etc., or made by coating nished metalarticles, Without departing from the spirit of my invention.

It is well known that it is very diiicult to unite, permanently, unlikemetals, such as wrought iron and the various steels, with metals ofunlike nature such as copper, silver, gold, aluminum, cupriferous alloysl(such as bronze, brass, etc.), aluminum alloys (such as aluminumbronze, manganese bronze, etc.) lt is also generally considered thatmetals of high melting-point cannot be cast at their ordinary castingtemperatures against a metal surface coated with a metal of low meltingtemperature such as tin, without causing detrimental oxidation,volatilization, or vaporization of the metal kof low meltingtemperature,due to the fact that the temperature necessary to bringV themetals of high melting temperature to a Acasting condition is suiiicientto oxidize,

volatilize, or vaporize the metal of low meltmg temperature, and preventa perfect union being formed. It has further hereto- `fore been foundnecessary in the art of coatlng metals with metals of high meltingpolntto protect a film coating secured from such metals or alloys fromcontact with the air, by neutral gases, vaporized atmospheres, chemicalsubstances of a solvent or protecting nature, etc., because thetemperatures heretofore necessary to secure such film coatings weresuciently high to cause oxidation or other detrimental action.

lt is one of the objects of my invention to eliminate thesenecessities.v

The fundamental discovery upon which my new process rests is that whileunlike metals and alloys of high melting temperatures, such as abovenamed, do not unite readily under the usual conditions of meltlng, andvolatilize metals of low melting temperature if cast thereagainst at theordinary castmg temperature of such high melt- 1ng metals; yet,ifcertain deoxidized and deoXidizing alloys of such high melting metals asabove referred to are maintained at a teniperature considerably belowthat at which they are usually cast, and the metals to be coated arepreviously coated with a metal or alloy of low melting temperature,detrimental oxidation, volatilization, and vaporization are avoided, andthe use of protecting apparatuses and added 4protecting manufacturedinfluences for the film coatings obtained are eliminated. The unionsecured is absolutely permanent, being'inseparable by change oftemperature such as heating to red heat and plunging into ice water; bycleaving tools, such as a cold chisel or like tool applied along theline of demarcation (the tool tending to dig into one metal or theother) and by distortion in any manner to Separate the joined metals;and the metals so joined permit extension to any degree by drawing,rolling, pressing, hammering, etc., without the slightest eX- foliation.

Deoxidized and deoxidizing alloys, by

lwhich l mean such alloys as aluminum bronze, at a temperature, whichmaybeA play extraordinary chemical or physical activity, readily unitingwith such metals dissimilar thereto as iron and steel, if the latter arepreviously coated with a metal or alloy of low melting temperature, suchas tin. N or do they cause,.or are. they themselves, when in thissemi-molten condition, subject to the detrimental infiuences whichprevent fr a union. between the dissimilar metals at the ordinarycasting temperatures of such alloys or dissimilar metals. While the factis as stated I am unable to .give an explanation of the henomenon.Possibly it is due to a catalytlc condition existing at thistemperature, or to some eutectic molecular charge accompanied by changesin physical properties. This peculiar increase of chemical activity ofsemi-molten deoxidized and deoxidizing alloys and the concomitantheightening of their affinity for certainl other metals, whether thesecharteristics be molecular, atomic, catalytic eutectic, orphysico-chemical, if heretofore observed has not to my knowledge beenapplied to the uniting of unlike metals of the classes hereincontemplated, and I am not aware that any attempt has ever been made toproduce between contacting surfaces' of metals to be joined a coating ofdeoxidizing metal at a temperature so low that detrimental oxidation ofthe film coating secured has been avoided and the use of addedmanufactured deoxidizing infiuences therefore eliminated.

As an illustration of a deoxidized and deoxidizing metal or alloy to beused as a coating and uniting film, a ten per cent. aluminum bronze maybe taken. This alloy has a casting temperature of about 1800 F. Aspractised in this invention, the semimolten condition exists at atemperature considerably below 1800 F.

In coating metal with molten metal by my process, the entire coatingneed not necessarily be of the deoxidized metal used as a linking nexusfor other metals, so long as the main coating desired has affinity forand will combine readily with the film coating. For example, whencoating a ferrous metal like steel, with copper, I first film-coat thesteel with tin, next with a deoxidized alloy such as aluminum bronze atsemi-molten temperature, and then cast against or contact with suchalloyed film-coated surface a metal such as copper at a convenientcasting temperature of the copper. The molten copper, being of metallike unto the film coating, and of higher temperature, combines readilywith the deoxidized and deoxidizing film coating, due to the powerfulaffinity, urifying, and reducing action created a ong the surface ofunion by the deoxidized metal previously applied. The

scavengin-,glgv and ldeoxidizing infiuenees, which, 1n the firstinstance, caused the removal of impurities, dissolved oxids, and yoccluded ases from the film coating, now prevent t e added molten coppertaking them up again alon the. line of union between the co per ansteel, securing a positive union, ree from flaws, ties or other defects.Nor wil re-heating of the joined bodies of unlike metals in furtherworking deteriorate in any manner the union along the surface of contactbetween the joined metals. In fact I have found thatthe metal along theplane of joinder is actually improved thereby. When the process isproperly carried out the alloying of the film coating along thc line ofjoinder of the copper and steel is confined to an excessively thin filmbetween approximate surfaces, the main portion of thc metals possessingtheir ordinary properties.

It is not essential in securing the film coating that'the article to becoated shall be confined for a long period of time in the bath ofsemi-molten deoxidized metal, and I have found that the thickness ofcoating secured (to a certain degree) is in direct .proportion to thelength of time that the articles are immersed in the semi-molten metal.In practice when I desire to use a film coating as a linking nexusbetween other metals, I usually use a coating of the thickness securedby slowly lowering and raising the article to be coated in and out of abath of the semi-molten metal, and do not leave it stationary in thebath any great length of time. Yet if a clean piece of tincoated steel,previously heated to a telnperature below the volatilizing or oxidizingtemperature of the tin on such steel, is passed rapidly in and out orthrough a bath of semi-molten deoxidized metal such as aluminum bronze,it will be found to be coated with a firm thin permanent cohering filmofthe deoxidized alloy, so thin, bright, smooth, and free from flaws,pores, etc., as to be scarcely perceptible to the eye. The coating sosecured, if subjected to a strong oxidizing infiuence for a long periodof time-will be found to develop the rich color of the deoxidized alloyused. In many cases this exceptionally thin film coating is sufficientto secure a union between other unlike metals, but I find that thechemical activities and aiiinities of the film coating are morepronounced for other metals if a film coating a little richer indeoxidized alloys is secured.

A film coating secured in the manner above described does not lose itsbrightness by atmospheric contamination as is common in the art ofworking metals of high melting temperature and it can be handled withperfect freedom in an oxidizing atmosphere such as air without fear ofcontamination ores, impurinreaaaa of the film-coating in any manner.vFhis has never been possible heretofore in the art of working metals ofthe class herein contemplated.

By my process, ll am enabled for the first time in the history of theart, ll believe, to

secure a union between unlike metals of highmelting temperature at atemperature so low that oxidation or contamination of the lmcoatingsecured is avoided, and the use of added manufactured protectingapparatuses and influences necessary in other processes (such as casingsof neutral gases, vaporized atmospheres, lchemical fluxes, and othersolvents of occluded gases and impurities) are eliminated. This is animportant feature in my invention, as it permits perfectv freedom ofinspection of the film-coating, and assures a high percentage ofperfectfinished products. It also permits rehandling of the coatedarticles at various stages of the process and counteracts negligence onthe partof the workmen employed.

ln practice, to determine when the semimolten. or operating conditionhas been reached, thin pieces of tin-coated steel wire may be kept handyand dipped into the metal from time to time and the coating securedexamined in the open air. lt is also easy by the latter method oftesting to determine when the limit of the semi-molten or operatingtemperature is exceeded, as the testing wire will then leave the bathuncoated and blackened to an excessive degree, and in this case, allthat is necessary is to reduce the heating and permit the molten metalto return to a semi-molten condition. ll have found however thataluminum bronze has a considerable range of plasticity between itsplastic and liquid condition and with a fair amount of attention on thepart of the operator little trouble is experienced. In the accompanyingdrawings, Figure 1- shows a cylindrical ingot in elevation, and anattached screw-eye for handling Fig. 2 is a -removable center to beinserted in the bottom of the ingot; Fig. 3 is an end View of the ingotin Fig. l; Fig. 4 shows the ingot centered in a mold; Figs. 5 and 6 aretop and side views of a top centering spider; Figs. 7 and 8 arelongitudinal and transverse views of a sectional mold showing anoctagonal-shaped ingot; Figs. 9 and 10 are views of its top centeringspider; Fig. 11 is a transverse view of a sectional mold for coatingsquare ingots; Fig. 12 is a similar view for coating rectangular ingots;Fig. 13 shows a two-compartment furnace in which the ingots receivepreliminary metallic coatings; Fig. 14 shows a film-coated ingot; Fig.15 shows a piece of coated steel separated close to the union; and Fig.16 shows a section of a compound ingot. A

ln illustrating my process, ll will use as an example the uniting ofcopper and steel,

and will assume that steel ingots are to becoated on all sides with asubstantial coat-V ing of copper and then extended by manufacture intosheets, rods, and other varieties by the usual methods of metal workingsuch as rolling, hammering, pressing, drawing, etc. For convenience inhandling the ingots have attached to them the rings 2 and bot. tomcenters 3.

A suitable number of steel ingots are rst thoroughly cleaned by sandblasting or. other mechanical means, and are then `pickled inhydrochloric or other non-oxyyfrom the bath and drying-room is now takento a second bath l which contains a lowmelting metal or alloy, such asmolten tin, at a temperature of fluidity commonly practised in tinning(see' Fig. 13). A quantity of commercial sal-ammoniac is thrown upon thesurface of the molten tin as the ingot is slowly lowered into the bath.After a short period of time depending upon the size of the ingot, theheat 0f the'tin, and the heat absorbed in the previous operations, theingot is raised a few inches out of the bath to see if the tin which hasAal strong affinity for steel under the conditions named, is coheringthereto in a very thin film and when this is observed to be the result,the ingotis drawn out ofv the bath through mechanical wipers in order toremove excess metal. llt is next carefully inspected for flaws and ifany are found this' last operation is repeated. After the tin coatedsteel ingot has passed inspection, and with its surface now heated toabout 400 F. from contact with the molten tin, it is taken to anotherbath 5, containing a pure grade of commercial copper to which three tofive per cent. (by weight) of commercially pure valuminum has been previously added. A higher orlower per cent. of aluminum may -be used as lldo not confine myself. to the specific proportions herein. This bath ofaluminum bronze is maintained, in the furnace 6 heated preferably by agas or oil-burner 6', in a semi-molten condition. The exact limits oftemperature of this semi-molten condition have not been determined, butby use of the test pieces, as above referred to, the operator willreadily ascertain when the proper condition has been reached. ll preferto use this bath the when it is in a state of medium plasticity, whichis obtained by first ymelting the alloy and then permitting it to coolIto the requisite degree. When the test pieces show that semi-moltenconditlon has been reached, the heat is again applied and regulated tomaintain the bath in this condition. I have worked with this bath up toa point where plasticity disappears, but I find that the tin-coatedsteel seems to slip through the deoxidized metal more freely at a lowertemperature. The tin-coated ingot is now slowly lowered and raised inand out of this bath 5 of semi-molten deoxidized alloy l without leavingit stationary therein any longer than necessary. On withdrawing the nowalloy-coated ingot 7 it will have been coated with a thin, firm,permanent, cohering film coating 8, shown greatly exaggerated, of themetals used, see Fig. 14:, and

this coating will be so thin, smooth, bright,

and free from flaws as to be barely perceptible at first glance. Noprotection from the action of the air need lbe provided as thefilmcoating has been secured at a temperature so low ,that it is notoxidized and is not subject to the detrimental influences which makeprotection necessary in other processes. The bright alloy-coated ingot,with its surface now more highly heated from contact with 'thesemi-molten bath of deoxidized alloy, is again inspected with perfectfreedom, and if satisfactory is centered in a cover 9 of an ingot mold10 used in the next operation.

It is then taken to this mold (Fig. 4) which contains molten copper ofextreme purity at its ordinary casting temperature and centered therein;or if desired, the copper 16 may be cast into the mold 10, through ports40 11, provided in the cover 9 for that purpose,

after the ingot has been centered in the mold 10.

The mold used is usually coated with a wash made from plumbago and waterdried by heating, and the molten copper therein on the steel ingotreadily combines therewith to form a perfect union, due to the powerfulaffinity, purifying and reducing action created along the line ofjoinder by the deoxidizing metal 5 previously applied o to the copper ofthe film-coating; and the scavenging and deoxidizing influences which inthe first instance removed from the copper of the film-coating theimpurities, oxids, dissolved oxids, and occluded gases, now have thesame effect on the added molten copper 16, along the surface of unionbetween the copper and steel.

As soon as the molten copper 16 has solidified to the extent that itwill permit handling, pressure-clamp 20 is removed, the eyelet 2 isreinserted, and the finished in ot is removed from the moldy andsubjecte to a soaking heat and worked into extended ware by the usualmethods of manufacture such as rolling, drawing, pressing, hammering,spinning, etc.,l or if desired the compound ingot of copper and steelmay be permitted to cool entirely, and be reheated and worked at somefuture time.

In Figs. 7 to 12, inclusive, are illustrated sectional molds ofdifferent cross-sections, for treating differentl shaped ingotsv 4orbillets, etc. The operation of coating the ingot is the same asdescribed for Fig. 4. The mold in Fig. 4 is shown tapering, vat 12,exaggerated for purposes of `illustration,in order to facilitate theremoval of the coated ingot. The mold 13 in Fig. 7, while shown slightlytapering, at 14, may if desired, be of uniform bore, since the molds maybe unbolted and removed from the ingot, instead of removing the latterfrom the top. With the sectional molds 13, the overlapping joints 145are first coated with a paste of graphite and oil, enabling an easyseparation of the sections, and preventing leakage of molten metal.

In Fig. 16 I have shown a. section of a compound metal body of unlikemetals produced according to my invention. The central portion 1` issteel, the outer portions 16 pure copper, and the film-coating 8 used asa linking nexus between the metals is a deoxidized alloy secured atsemi-molten temperature. The film-coating 8 or linking nexus, as shown,is greatly exaggerated for the purpose of illustration.

While I have specified copper and steel as the metals used, the sameprocess is applicable to coating or combining other metalsione withanother. No added manufactured protections or -non-metallio substancesof a protecting, fluxing, or solvent nature are necessary to protect thefilmcoating 8 in any manner, or cause the added copper to combinetherewith.

The test piece shown in Fig. 15 was cut from the body illustrated inFig. 16, parallel to the union between the copper 16 and steel 1, wasalso rolled parallel t'o the union to flatten it, then heated to redheat three times and plunged into ice water each time, and was thendistorted by bendingl until the metals broke, the break occurringadjacent the line of union between the joined metals and in no mannerindicating a rupture along the line of' demarcation. This line ofdemarcation between the joined metals does not give any ordinary visibleevidence of the previous presence of the film-coating re- ICS .lll

ferred to, the -contacting surfaces being combined so thoroughly thatthe metals joined appear to be pure copper and steel.

In coating metals with other metals of unlike nature the base or coremetal l need not necessarily be of iron or steel, as I can combine bythe method herein ldescribed any metals which readily accept afilmcoating of a deoxidized metal secured at semi-molten temperature. Itis also obvious that all sides of film-coated articles need not becoated with the same metal, for as is well known a protector may be usedto protect one or more sides of the film-coated article from a metalapplied, the protector removed, or partly removed, and another unlikemetal applied to the surface then eX- posed, and in coating metals bythe, process described, it is readily seen that with a film# coatingsecured in the manner stated, the metal caused to combine therewith neednot be in an entire state of fusion as the contacting surface of themetals to be applied need only be brought to a temperature sufficientlyhigh to cause combining with the deoXidized film-coating secured atsemimolten temperature.

By the term ferrous metal in certain of the claims herein, I designateall forms of iron or steel, which will readily accept a deoxidizedfilm-coating at semi-molten temperature under the conditions named; andby the term tin I designate a metal such as tin, of low melting-point,that may be used for coating ferrous metals, as described herein; and bythe term metallic substance I mean metals or alloys as described herein.I do not confine myself necessarily to pure metals, as certainmodifications thereof can be used with fair re- .sultsz I have alsoapplied such metal of low melting temperature by precipitation, but asthis method does not accomplish the preliminary heating necessary toprevent an undue amount of heat being abstracted from the semi-moltendeoxidized metal, I prefer to use a metal of low melting-point in amolten condition. By the clause added manufactured protectingapparatuses and influences, I mean to designate the protectors generallyconsidered necessary in this art to protect a film coating of metalshaving a melting-point above 900 I". from detrimental atmosphericaffection, also the added applied non-metallic constituents used toprotect filmcoatings or cause other metals to combine therewith.

I claim l. A compound metal body, comprising a plurality of layers ofmetallic substances united on their contacting surfaces by a deoXidiZingmetallic substance.

2. A compoundmetal body, comprising a base metal, a deoxidizing metalliccoating thereon, and another metallic substance united to' said basemetal by said coating.

3. A compound metal body, comprising a base metal,a coating of alow-melting-point metal thereon, a second coating of ade-` oxidizingmetallic substance, and another metal united to said deoxidizingmetallic substance.

4. A compound metal body, comprising a ferrous base metal, a coating ofa low-melting-point metal thereon, a second coating containing adeoxidizing metal and an alloying metal, and a layer of said alloyingmetal upon said second coating.

5. A compound metal body, comprising a ferrous base metal, a coating oftin thereon, a coating of an alloy containing a deoXidizing metal andcopper upon the t'in, and a layer of copper upon said alloy.

6. A compound metal body, comprising a ferrous base metal, a coating oftin thereon, a coating of aluminum bronze upon the tin, and a layer ofcopper upon the aluminum bronze.

In testimony whereof I afiiX my signature in presence of two witnesses.

OTT() I-I. DE LAPO'ITERIE.

I/Vit'nesses:

E. I?. lPA'roN, II. S. I-IAMTORNE.

